Android Developers Blog

Posted by Hoi Lam, Lead Developer Advocate, Android Wear
Today we launched the latest version of the Android Wear SDK (2.2.0) with several watch face related enhancements. These include the addition of an unread notification indicator for all watch faces, which is planned to be part of the upcoming consumer release of Android Wear. With the Wear SDK 2.2.0, you can customize the notification indicator or display your own. This feature is available to the developer community early, via the SDK and emulator, so you can verify that the indicator fits the design of your watch face. In addition, we are adding enhancements to the ComplicationDrawable class and publishing the final version of the Wear emulator based on Android Oreo.

Introducing the unread notification indicator

Notification is a vital part of the Wear experience. As a result, starting from the next consumer release of Wear (version 2.9.0), a dot-shaped indicator will be displayed by default at the bottom of the watch face if there are new, unread notifications. Watch face developers can preview the indicator with their watch faces by using the latest version of the emulator. Developers can customise the indicator's accent color via WatchFaceStyle.setAccentColor - the default color is white as shown in the example below, but developers can set the color for the ring around the dot to an accent color of their choice, to match the rest of the watch face.
If the new indicator does not fit with the design of your watch face, you can switch it off using WatchFaceStyle.setHideNotificationIndicator and choose another option for displaying the notification, including: 1) displaying the number of unread notifications in the system tray using WatchFaceStyle.setShowUnreadCountIndicator, or 2) getting the number of unread notifications using WatchFaceStyle.getUnreadCount and displaying the number in a way that fits your watch face's unique style.

Enhancement to ComplicationDrawable

We launched the ComplicationDrawable class at last year's Google I/O, and we are continuing to improve it. In this latest SDK release, we added two enhancements:

Permission Handling - If the watch face lacks the correct permission to display the content of a complication, the complication type of TYPE_NO_PERMISSION is issued. ComplicationDrawable now handles this automatically and will launch a permission request in onTap. If you previously implemented your own code to start the permission screen, please check that the permission screen is not triggered twice and, if necessary, remove unneeded code.

Drawable Callback - If a complication contains an image or an icon, it can take a small amount of time to load after the other initial data arrives. Our previous recommendation therefore was that you redraw the screen every second. But this is unnecessary for watch faces that only update once per minute, for example. As a result, we have added new support for Drawable.Callback to ComplicationDrawable. Developers who update the screen less frequently than once per second should adopt this new callback to redraw the watch face when images have loaded.

More improvements to come

Many of you have noticed a steady release of enhancements to Android Wear over the last few months since the launch of Wear 2.0. We are developing many more for the months ahead and look forward to sharing more when the features are ready.